KR100278373B1 - Magnetic recording reproducing apparatus - Google Patents

Abstract

According to the present invention, when the drive motor is provided on the upper cylinder, the amount of magnetic flux from the drive motor jumping into the audio head is reduced, or the attachment phase of the control board and the attachment phase of the magnetic collecting member are reduced. It is a technical problem to provide a magnetic recording and reproducing apparatus which can reduce the deterioration of characteristics with respect to dispersion and can also be made at low cost.

Solution for this is made by installing the drive coil on the fixed drum 11 side, the rotor magnet 22 on the rotating drum 15 side, the drive motor (M) for driving the rotating drum (15) And a stator board 31 on which a control circuit for controlling the drive coil of the motor M is mounted, an audio head Hc provided in the vicinity of the fixed drum 11, and a drive coil of the motor M; While the substrate 31 is disposed on the fixed drum 11 side so as to be positioned above the rotating drum 15, the head Hc is located in the region of the substrate 31 opposite to the rotation center of the motor M. The collector member 37 which collects the magnetic flux Φ was disposed.

Description

Magnetic recording and playback device {MAGNETIC RECORDING REPRODUCING APPARATUS}

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a magnetic recording and reproducing apparatus in which a driving head for driving a rotating drum is disposed on a cylinder such as a VTR, so that the audio head is not affected by the magnetic flux from the driving motor.

4 is a plan view of a main portion of the tape running portion of the tape player using a rotating head device such as a general video tape recorder (VTR).

The rotary head device 1 is provided with a rotary drum 2 which is driven by a drive motor, and the magnetic heads H1, H2, H3 and H4 are mounted on the rotary drum 2. The magnetic tape T drawn out from the supply side tape reel is guided to the guide posts 3a and 3b and the loading post 3c, wound around the rotary head device 1 at a predetermined angle, and again loaded with the loading post 3d. Guided by the guide posts 3e and 3f, it is sandwiched between the capstan 4 and the pinch roller 5, and it drives in the arrow direction shown by the rotation of the capstan 4. As shown in FIG.

In addition, as the fixed head, the full width erase head Ha, the voice erase head Hb, and the voice / control head Hc are provided. Of these fixed heads, the voice / control (audio) head (Hc) is the one that dislikes noise the most. This is because when noise is applied to the head Hc, this is superimposed on the reproduced audio as audio noise.

By the way, the cylinder used in the VTR has become mainstream because of the structural advantages, the shaft fixing type in which the drive motor is located on the upper side of the cylinder. In this shaft fixing method, since the drive motor is disposed in the upper portion of the cylinder, the drive motor is not blocked by a chassis or the like spatially between the audio head Hc provided in the VTR, and also closes in distance. As shown in Fig. 5, there has been a problem that the magnetic flux Φ generated by shaping is easily jumped into the audio head Hc according to the arrangement of the drive coils (not shown) of the drive motor.

As a countermeasure against this, in the cost problem, as shown in FIG. 6, there is a method of attaching a shielding plate. In Fig. 6, reference numeral 6 denotes a shielding plate attached to the rotary drum 2, reference numeral 7 denotes a drive motor comprising a stator core 7a and a driving magnet 7b, reference numeral 8 denotes a fixed shaft, and reference numeral 9 denotes a fixed drum.

However, in the structure shown in FIG. 6, the shielding plate 6 cannot be sufficiently covered, and the influence of the magnetic flux Φ leakage of the drive motor 7 to the audio head Hc cannot be prevented. In addition, since the shielding plate 6 is provided in the vicinity of the outer circumference of the rotary drum 2, there is a problem that the rotational balance becomes unbalanced, the distribution of the inertia becomes the outer circumference, and the disturbance of the rotary drum 2. It became a factor.

Alternatively, in the case of using a shielding plate that covers the entire driving motor 7, a short preventive measure with a drive circuit on the driving motor 7 is required, and the shape of the shielding plate is increased, resulting in molds due to the complexity of the shape. The cost of an apparatus becomes considerably high by the price increase of the shielding board itself by multiple processes, etc.

The first object of the present invention is to reduce the amount of magnetic flux from the drive motor jumping into the audio head when the drive motor is provided on the cylinder, or to disperse the attachment phase of the control board or the attachment phase of the magnetic collecting member. The present invention also provides a magnetic recording and reproducing apparatus which can reduce deterioration of characteristics and can be made at low cost.

A second object of the present invention is to provide a magnetic recording and reproducing apparatus which can be easily fixed by adhering the magnetic collecting member onto a driving IC and shielding the leakage magnetic flux in the driving IC.

BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is an exploded perspective view showing main parts of an embodiment of a magnetic recording and reproducing apparatus according to the present invention;

2 is a longitudinal sectional view of an embodiment of a magnetic recording and reproducing apparatus according to the present invention;

3 is an explanatory diagram showing a state of a leaked magnetic flux by a drive motor of one embodiment of a magnetic recording and reproducing apparatus according to the present invention;

4 is an explanatory diagram showing a part of a tape traveling path in a rotating head device portion such as a general VTR;

5 is an explanatory diagram showing a state of leakage magnetic flux by a drive motor of a conventional magnetic recording and reproducing apparatus; And

6 is a longitudinal sectional view showing a conventional magnetic recording and reproducing apparatus.

Explanation of symbols on the main parts of the drawings

11: fixed drum 12: fixed shaft

15: rotating drum 22: rotor magnet

31 stator substrate 36 drive IC

37: house member M: drive motor

Hc: audio head

The said 1st subject is a fixed drum which fixed the shaft, the rotating drum freely supported by the shaft of the said fixed drum, and fixed the drive coil to the said shaft, and installs the drive magnet in the said rotating drum facing the said drive coil. And a control board on which a drive motor for driving the rotating drum, a control circuit for controlling a drive coil of the drive motor is mounted, and an audio head provided in the vicinity of the fixed drum, and a drive coil of the drive motor. And a dust collecting member for collecting magnetic flux in an area of the control board which is disposed on the fixed drum side so that the control board is positioned above the rotating drum, and which is located opposite to the center of rotation of the drive motor. Is achieved by the first means arranged.

The second problem is that, in the first means, the driving IC is disposed in an area of the control substrate which is located on the side opposite to the center of rotation of the driving motor with the audio head, and at the top of the driving IC. It is achieved by the second means which arranged the member.

Moreover, the said 1st subject is achieved by the 3rd means which is the plate piece which the said magnetic collecting member becomes from a ferromagnetic material in a 1st means.

EMBODIMENT OF THE INVENTION Hereinafter, one Embodiment of this invention is described.

1 is an exploded perspective view showing main parts of an embodiment of a magnetic recording and reproducing apparatus according to the present invention, FIG. 2 is a longitudinal sectional view of an embodiment, and FIG. 3 is an explanatory diagram showing a state of a leakage magnetic flux by a drive motor of an embodiment. to be. In addition, since the tape running path shown in FIG. 4 is the same in this embodiment, detailed description is abbreviate | omitted.

In Fig. 1 and Fig. 2, reference numeral 11 denotes a fixed drum, and a fixed shaft 12 is fixed to the fixed drum 11 by fitting means. On the outer circumference of the fixed shaft 12, the rotation drum 15 is freely supported by a pair of bowl shaft numbers 13 and 14. A plurality of head bases 16 are fixed to the outer periphery of the bottom face of the rotary drum 15, and a magnetic head H for recording / reproducing video signals is fixed to each head base 16.

At the upper end of the fixed shaft 12, a drive motor M for rotating the rotary drum 15 is provided. The rotor R of this motor M is being fixed to the upper surface of the rotating drum 15. As shown in FIG. In addition, the stator S is fixed via the fixed push 17 at the upper end of the fixed shaft 12.

In the rotor R, the rotor magnet 22 is fixed to the inside of the rotor yoke 21 made of sheet metal formed in a concave shape. As shown in Fig. 2, the rotor magnet 22 is formed in an L-shaped ring shape in cross section, and its inner circumferential surface is alternately magnetized with N magnetic poles and S magnetic poles alternately facing the circumferential direction. It is a magnetic surface 22a. The bottom face of the rotor magnet 22 is a PG magnetizing portion 22b in which magnetic poles are magnetized at one or two circumferential positions. This PG magnetizer is for detecting the rotational phase of the rotor R. As shown in FIG.

In the bottom face 21a of the rotor yoke 21, an insertion hole 21b through which the fixed shaft 12 is inserted upward is formed, and a positioning groove 21c is formed at one place of the outer circumference. . Moreover, the positioning projection 15b is formed in the rotor installation surface 15a of the upper surface of the said rotating drum 15, and this positioning projection 15b and the said positioning groove 21c are couple | bonded, and a rotating drum The phase of 15 and rotor R are combined. In this state of phase coupling, the attachment screws 23 and 23 (see Fig. 2) are inserted into the attachment holes 21d and 21d formed through the rotor yoke 21, and the rotor mounting surface of the rotating drum 15 ( The rotor R and the rotating drum 15 are fixed to each other by screwing into the male screw holes 15c and 15c of 15a).

The stator board | substrate 31 is provided in the said stator S, and this stator board | substrate 31 was formed with resin, a ceramic, etc., The upper surface becomes the mounting surface 31a of the electronic component in which the conductive pattern was formed.

As shown in FIG. 2, the fixed push 17 is fixed to the upper surface of the fixed shaft 12 by a headless screw 18, and the stator substrate 31 is attached to the fixed push 17. It is fixed by the screws 32 and 32.

The ring-shaped magnetic member 33 is fixed to the lower surface of the stator substrate 31 by means of adhesion or the like through the magnetic yoke 34. On the outer circumference of the magnetic member 33, a plurality of stator cores 35 protrude radially, and a stator coil (drive coil) is wound around each stator core 35 although not shown.

In addition, the driving IC 36 is mounted on the mounting surface 31a of the stator substrate 31. This drive IC 36 is provided on the left side of the fixed shaft 12 as shown. In addition, the magnetic strip member 37 is adhered and fixed to the upper portion of one driver IC 36 as if the driver IC 36 is covered.

The magnetic collecting member 37 is made of a ferromagnetic material, for example, a tin plated steel sheet, and is arranged in the region of the control board positioned opposite to the center of rotation of the drive motor with the audio head Hc. As shown in FIG. 3, the magnetic flux member 37 collects the leakage magnetic flux Φ in the drive motor M, so that the leakage magnetic flux Φ is biased so as to be tensioned on the magnetic field member 37 side. The leakage magnetic flux Φ to the side where the audio head Hc is arranged is reduced. Therefore, the audio head Hc can reduce the influence of the leakage magnetic flux Φ in the drive motor M. FIG.

A connector 43 is mounted on the upper surface of the stator board 31, and the connector 43 is connected to the stator coil or the like via a conductive pattern formed on the mounting surface 31 a.

In such a rotating head apparatus, the center line 0 of the fixed shaft 12 is fixed on the chassis of the tape player in a state inclined by θ with respect to the vertical line. Therefore, the stator board | substrate 31 also inclines by (theta) with respect to the horizontal line L parallel to a chassis.

In such embodiment, the fixed drum 11 which fixed the fixed shaft 12, the fixed drum 15 by which rotation was supported by the fixed shaft 12 of the fixed drum 11 freely, and the fixed drum 11 The drive coil is provided on the side, and the rotor magnet (drive magnet) 22 is provided on the rotating drum 15 side, and the drive motor M which drives the rotating drum 15, and the drive motor M, A stator board (control board) 31 mounted with a control circuit for controlling the drive coil, and an audio head Hc provided in the vicinity of the fixed drum 11, and a drive coil and a stator board of the drive motor M ( 31) the area of the stator substrate 31 which is disposed on the fixed drum 11 side so as to be located above the rotating drum 15, and which is located on the side opposite to the center of rotation of the drive motor M as the audio head Hc. On the collector member (eg, collector member) for collecting magnetic flux (Φ) Since the plate piece which consists of ferromagnetic materials 37 is arrange | positioned, when the drive motor M is installed in a cylinder upper part, the drive motor M is only provided by providing the condensing member 37 of a space-savingly simple structure. Since magnetic flux Φ in the magnetic field is collected toward the magnetic collecting member 37, the characteristics are also strong with respect to the dispersion of the attachment phase of the stator substrate 31 and the adhesion phase of the magnetic collecting member 37, and certainly the audio head ( The influence of the magnetic flux Φ on the drive motor M to Hc) can be reduced, and the cost can be reduced.

In the above embodiment, the drive IC 36 is disposed in the region of the stator substrate 31 located on the side opposite to the center of rotation of the drive motor M from the audio head Hc. Since the magnetic collecting member 37 is disposed on the upper portion of the upper surface of the magnetic collecting member 37, the magnetic collecting member 37 can be easily fixed by sticking on the driving IC 36, and the leakage magnetic flux? In the driving IC 36 can be fixed. It can also shield.

As described above, according to the first and third aspects of the present invention, in the case where the drive motor is installed in the upper portion of the cylinder, the magnetic flux in the drive motor is collected only by providing a condenser member having a space-saving and simple structure. As a result, the characteristics of the control board are increased, and the dispersion of the mounting position of the magnetic strip member becomes stronger, and the influence of the magnetic flux on the drive motor of the audio head can be reliably eliminated, and the cost can be reduced. .

According to the second aspect of the present invention, in addition to the effect of the first aspect, since it is disposed above the driving IC, the magnetic element member can be easily fixed by sticking on the driving IC, and the leakage of the driving IC is further reduced. Magnetic flux can be shielded.

Claims (3)

A fixed drum fixed to the shaft, A rotating drum freely supported by a shaft of the fixed drum, A driving motor fixed to the shaft and provided with a driving magnet in the rotating drum to face the driving coil, the driving motor driving the rotating drum; A control board mounted with a control circuit for controlling a drive coil of the drive motor; An audio head provided in the vicinity of the rotating drum, At the same time as the drive coil and the control substrate of the drive motor is disposed on the fixed drum side to be located above the rotary drum, And a magnetic collecting member for collecting magnetic flux in an area of the control board which is located opposite to the center of rotation of the drive motor from the audio head. 2. The drive head according to claim 1, wherein a drive IC is disposed in an area of the control substrate located opposite to the center of rotation of the drive motor, and the magnetic member is disposed on the drive IC. Magnetic recording and reproducing apparatus. The magnetic recording and reproducing apparatus according to claim 1, wherein the magnetic collecting member is a plate piece made of a ferromagnetic material.

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